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Werk #8557: Alert handling: Fixed repeating error "OSError: [Errno 9] Bad file descriptor"

Component The Checkmk Micro Core
Title Alert handling: Fixed repeating error "OSError: [Errno 9] Bad file descriptor"
Date Oct 19, 2016
Level Prominent Change
Class Bug Fix
Compatibility Compatible - no manual interaction needed
Checkmk versions & editions
1.4.0i2 Checkmk Enterprise (CEE), Checkmk MSP (CME)

This error occured when a helper was terminated or not really started and persisted until the alert helper was restarted (e.g. with cmk -R) and prevented othr event handlers from working correctly.

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